Apparatus for producing a stream of partly lapping sheets



Nov. 1, 1966 B. A. BOLTON 3,282,587

APPARATUS FOR PRODUCING A STREAM OF PARTLY LAPPING SHEETS Filed May 27,1964 United States Patent Ofifice 3,282,587 Patented Nov. 1, 19663,282,587 APPARATUS FOR PRODUCING A STREAM OF PARTLY LAPPING SHEETSBrian Albert Bolton, Ashford, Middlesex, England, as-

signor to Morane Plastic Company Limited, Ashford, Middlesex, England, aBritish company Filed May 27, 1964, Ser. No. 370,572 Claims priority,application Great Britain, Dec. 23, 1963, 50,765/ 63 7 Claims. (Cl.271-50) The invention relates to sheet feeding apparatus and moreparticularly to an apparatus for producing a stream of partly lappingsheets.

The invention provides apparatus for use in producing a stream of partlylapping sheets and for feeding the stream to a machine for operating onthe stream of sheets, which apparatus comprises feeding means forfeeding the stream to the machine, a stop member in the path of thesheets operative, during movement of a first sheet, to hold back asucceeding sheet lapped with the first to an excessive amount, until thelap is reduced to the desired amount and then to release the secondsheet to allow the two sheets to move together in lapping relation.

The invention further provides apparatu for feeding a succession ofsheets in underlapping relation to a laminating machine comprising meansto feed a succession of sheets along a feed path to the machine, a stopmember movable into the feed path from below the feed path which memberis operable to lift a first sheet which is passing over the memberwithout stopping the feed of the first sheet and to stop the nextsucceeding sheet, with its leading edge below the said first sheet,means to move the stop member into and out of the feed path insynchronism with the feed of the sheets along the path whereby the stopmember is moved into the path as a first sheet is passing over themember and is moved out of the path of the next succeeding sheet beforethe one sheet has moved completely past the stop member.

In one embodiment the feeding means is in two sections, one before andthe other after the stop member in the'path of the sheets, means beingprovided for rendering the first section ineffective while the stopmember is holding back a sheet and to render this section effective whenthe stop member has released the sheet.

It is preferred that the section of the feeding means before the stopmember in the path of the sheets comprises a conveyor to which thesheets are held by suction, means being provided to operate the suctiononly when the stop member has released the sheet.

The stop member may be moved into and out of the path of the sheet bymeans of a solenoid.

The movement of the stop member into and out of the path of the sheetmay be controlled by a timing device driven by the machine whereby theamount of lapping of the sheets remains constant when the speed of themachine is varied.

Preferably there is a variable speed connection between the timingdevice and the machine whereby the amount of lapping may be varied.

The machine may be a machine for laminating a succession of sheets to aweb as described in United States patent specification No. 714,335 nowU. S. Patent No. 2,916,444.

A specific example of apparatus according to the invention for feedingsheets in underlapping relation to a laminating machine will now bedescribed with reference to the accompanying drawing which is a sideelevation of the machine embodying the sheet feed apparatus.

The laminating machine 10 comprises essentially two pressure rollers 11and 12 which are spring urged towards one another and a table 14. Asuccession of sheets in underlapping relation passing across the table14 and an overlying web of backing paper (e.g. of plastic film or foil)are fed to the nip between the rollers 11 and 12.

The backing paper is fed downwardly from a supply roller which is notshown.

A pool of adhesive is maintained between the web of backing paper andthe sheets adjacent the nip between the rollers 11 and 12 and as thesheets and the backing paper pass between the rollers, the sheets arelaminated to the backing paper. It will be appreciated that as a pool ofadhesive is maintained between the sheets and web, the sheets must befed to the rollers in underlapping relation or the adhesive will leakout between the sheets.

The apparatus for feeding the sheets in underlapping relation to therollers 11 and 12 will now be described A supply of sheets are stackedon a table 15 and the height of the table 15 is adjustable, by means ofa foot treadle or an electric motor.

Adjacent the table 15, there is a platform 16 formed by the surface of aperforated conveyor belt 17 which is taken round rollers 18, 19 and 20.At the machine end of the conveyor 17, there are a number of stopmembers 21, extending in a line across the machine transversely to thedirection of the feed of the sheets. The stop members 21 are attached tothe armature 22 of a solenoid 23 by means of a lever 24 pivoted at 25.

Below the perforated conveyor belt 17, there are a number of vacuum boxe26, one box being associated with each stop member 21 and the vacuumboxes 26 are evacuated by means of a vacuum pump (not shown) operatingthrough magnetically operated valves 29, there being one valve for eachvacuum box 26.

The magnetic valves 23 and hence the evacuation of the vacuum boxes 26and also the movement of the stop members 21 are controlled by avariable speed unit 32 which is driven from the main drive of themachine 10.

There are two rollers 30 and 31 to feed sheets over the table 14.

The operation of the apparatus for feeding sheets in underlappingrelation to the machine will now be described.

A stack of sheets is placed on the table 15 and the top sheet of thestack is arranged to be level with the platform 16, using the foottreadle or electric motor. The top sheet of the stack is fed manually onto the platform 16 and is placed with its leading edge against the stopmembers 21. The unit 32 operates the solenoid 23 to retract the stopmembers 21 and at the same time operates the valves 29 to evacuate thevacuum boxes 26 so that the conveyor belt 17, which is drivencontinually by the machine, conveys the sheet on the platform 16 intothe nip between the rollers 30 and 31 from whence the sheet is fed tothe table 14 and into the laminating machine proper.

As soon as the sheet has passed into the nip between the rollers 30 and31, the unit 32 moves the stop member 21 back into the position shown inthe drawing where they are in the path of the sheets and the evacuatingvalve 29 is once again closed.

It will be appreciated that moving the stop members 21 ino the feed pathof the sheet will not stop the movement of a sheet which has alreadypassed into the nip between the rollers 30 and 31.

As soon as the machine operator sees that the first sheet is moving intothe machine he places a second sheet on the platform 16 in underlappingrelation with the first sheet so that the second sheet abuts the stopmembers 21, and so soon as the first sheet has reached a position wherethe underlap between the sheet has been reduced to a predeterminedamount, the unit 32 again operates to move the stop members 21 out ofthe feed path and to evacuate the vacuum boxes 26.

The second sheet is now fed to the machine. It will be seen that theamount of underlap between the two sheets is controlled by the timing ofthe operation of the unit 32. By variation of the speed of the unit 32,the amount of underlap can be varied. Further, as the unit 32 is drivenfrom the main drive of the main machine, the underlap between successivesheets will remain the same if the speed of the main machine is altered.

I claim:

1. In combination with a machine for operating on a stream of partlylapping sheets, means for feeding the stream to the machine, meansdefining a path for the stream of sheets so fed, a stop member movableinto and out of the path and operable when in the path to hold back asheet lying intermediate in the stream and means operating in timedrelation with the feeding means to move the stop member into the pathbehind the front edge of each sheet in turn to hold back the next sheetand out of the path when that edge has advanced a predetermined distancefrom the stop member and from the sheet so held back, said distancebeing of such a magnitude that the rear end of said first sheet islapped over the front edge of the sheet so held back when-the stopmemher is withdrawn.

2. In combination with a machine for laminating a stream of partlyunderlapping sheets, means for feeding the stream to the machine, meansdefining a path for the stream of sheets so fed, a stop member movableinto and out of the path and operable when in the path to hold back asheet lying intermediately in the stream and means operating in timedrelation with the feeding means to move the stop member into the pathfrom below the feed path behind the front edge of each sheet in turn tohold back the next sheet and out of the path when that edge has advanceda predetermined distance from the stop member and from the sheet so heldback said distance being of such a magnitude that the rear end of saidfirst sheet is lapped over the front edge of the sheet so held back whenthe stop member is withdrawn.

3. In combination with a machine for laminating a stream of partlyunderlapping sheets, means for feeding the stream to the machine, meansdefining a path for the stream of sheets so fed, a stop member movableinto and out of the path and operable when in the path to hold back asheet lying intermediate in the stream and means operating in timedrelation with the feeding means to move the stop member into the pathfrom below the feed path behind the front edge of each sheet in turn tohold back the next sheet and out of the path when that edge has advanceda predetermined distance from the stop member and from the sheet so heldback, said feeding means being in two sections, one before and the otherafter the stop member in the path of the sheets, the section before thestop member having means which render the section effective only whenthe stop member is out of the path of the sheets.

4. In combination with a machine for laminating a stream of partlyunderlapping sheets, means for feeding the stream to the machine, meansdefining a path for the stream of sheets so fed, a stop member movableinto and out of the path and operable when in the path to hold back asheet lying intermediate in the stream and means operating in timedrelation with the feeding means to move the stop member into the pathfrom below the feed path behind the front edge of each sheet in turn tohold back the next sheet and out of the path when that edge has advanceda predetermined distance from the stop member and from the sheet so heldback, said feeding means being in two sections, one before and the otherafter the stop member, the section before the stop member comprising aconveyor and suction means which hold the sheets to the conveyor andwhich render the section effective only when the stop member is out ofthe path of the sheet.

5. In combination with a machine for laminating a stream of partlyunderlapping sheets, means for feeding the stream to the machine, meansdefining a path for the stream of sheets so fed, a stop member movableinto and out of the path and operable when in the path to hold back asheet lying intermediate in the stream and means operating in timedrelation with the feeding means to move the stop member into the pathfrom below the feed path behind the front edge of each sheet in turn tohold back the next sheet and out of the path when that edge has advanceda predetermined distance from the stop member and from the sheet so heldback, and a solenoid which moves the stop member into and out of thepath of the sheet.

6. In combination with a machine for laminating a stream of partlyunderlapping sheets, means for feeding the stream to the machine, meansdefining a path for the stream of the sheets so fed, a stop membermovable into and out of the path and operable when in the path to holdback a sheet lying intermediate in the stream and means operating intimed relation with the feeding means to move the stop member into thepath from below the feed path behind the front edge of each sheet inturn to hold back the next sheet and out of the path when that edge hasadvanced a predetermined distance from the stop member and from thesheet so held back, and means for varying the predetermined distanceaforesaid.

7. In combination with a roller machine for laminating a stream ofpartly underlapping sheets, means for feeding the stream to the machine,means defining a path for the stream of sheets so fed, a stop membermovable into and out of the path and operable when in the path to holdback a sheet lying intermediate in the stream, a solenoid operable tomove the stop member into the path from below the feed path behind thefront edge of each sheet in turn and out of the path when that edge hasadvanced a predetermined distance from the stop member, switch meanscontrolling operation of the solenoid, means for operating the switchand a variable speed drive from the machine to the switch operatingmeans, the feeding means being in two sections, one before and the otherafter the stop member, the section before the stop member comprising aconveyor and suction means operable to hold the sheets to the conveyorto render the section effective, only when the stop member is out of thepath of the sheets.

References Cited by the Examiner FOREIGN PATENTS 688,543 3/1953 GreatBritain.

M. HENSON WOOD, IR., Primary Examiner.

A. N. KNOWLES, Assistant Examiner.

1. IN COMBINATION WITH A MACHINE FOR OPERATING ON A STREAM OF PARTLYLAPPING SHEETS, MEANS FOR FEEDING THE STREAM TO THE MACHINE, MEANSDEFINING A PATH FOR THE STREAM OF SHEETS SO FED, A STOP MEMBER MOVABLEINTO AND OUT OF THE PATH AND OPERABLE WHEN IN THE PATH TO HOLD BACK ASHEET LYING INTERMEDIATE IN THE STREAM AND MEANS OPERATING IN TIMEDRELATION WITH THE FEEDING MEANS TO MOVE THE STOP MEMBER INTO THE PATHBEHIND THE FRONT EDGE OF EACH SHEET IN TURN TO HOLD BACK THE NEXT SHEETAND OUT OF THE PATH WHEN THAT EDGE HAS ADVANCED A PREDETERMINED DISTANCEFROM THE STOP MEMBER AND FROM THE SHEET TO HOLD BACK, SAID DISTANCEBEING OF SUCH A MAGNITUDE THAT THE REAR END OF SAID FIRST SHEET ISLAPPED OVER THE FRONT EDGE OF THE SHEET SO HELD BACK WHEN THE STOPMEMBER IS WITHDRAWN.